From c127a2a1b7baa5eb40a7e2de4b7f0c51ccbbb2ef Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Sun, 6 Sep 2020 00:45:15 +0300 Subject: [PATCH] io_uring: fix linked deferred ->files cancellation While looking for ->files in ->defer_list, consider that requests there may actually be links. Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe --- fs/io_uring.c | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 6129c67b0e3b..175fb647d099 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -8024,6 +8024,28 @@ static bool io_match_link(struct io_kiocb *preq, struct io_kiocb *req) return false; } +static inline bool io_match_files(struct io_kiocb *req, + struct files_struct *files) +{ + return (req->flags & REQ_F_WORK_INITIALIZED) && req->work.files == files; +} + +static bool io_match_link_files(struct io_kiocb *req, + struct files_struct *files) +{ + struct io_kiocb *link; + + if (io_match_files(req, files)) + return true; + if (req->flags & REQ_F_LINK_HEAD) { + list_for_each_entry(link, &req->link_list, link_list) { + if (io_match_files(link, files)) + return true; + } + } + return false; +} + /* * We're looking to cancel 'req' because it's holding on to our files, but * 'req' could be a link to another request. See if it is, and cancel that @@ -8106,8 +8128,7 @@ static void io_cancel_defer_files(struct io_ring_ctx *ctx, spin_lock_irq(&ctx->completion_lock); list_for_each_entry_reverse(de, &ctx->defer_list, list) { - if ((de->req->flags & REQ_F_WORK_INITIALIZED) - && de->req->work.files == files) { + if (io_match_link_files(de->req, files)) { list_cut_position(&list, &ctx->defer_list, &de->list); break; }